West Pacific/2015/09W/Archive/11
Public advisory TYPHOON CHAN-HOM PUBLIC ADVISORY NUMBER 11 WIKI-HURRICANES FORECASTING CENTER 12:00 AM JST FRI JUL 03 2015 ...CHAN-HOM REGAINS COMPOSURE AND BECOMES A TYPHOON... ...SIGNIFICANT THREAT TO THE MARIANA ISLANDS... SUMMARY OF 12:00 AM JST...15:00 UTC...INFORMATION ------------------------------------------------------------------- LOCATION...10.0N, 148.0E CENTER POSITION CONFIDENCE: HIGH ... ± 25 MI... 40 KM ABOUT 325 MI...520KM SE OF HAGATNA, GUAM MAXIMUM SUSTAINED WINDS...65 KT...75 MPH...120 KM/H MINIMUM BAROMETRIC PRESSURE...985 MB...29.09 INCHES PRESENT MOVEMENT...WSW AT 10 KT...11 MPH...19 KM/H DISCUSSION AND 48-HOUR OUTLOOK --------------------------------------------- At 12:00 am JST, the center of Typhoon Chan-Hom was situated near 10.0N, 158.0E, or about 325 miles (520 kilometers) southeast of Hagatna, Guam. Maximum sustained winds were 65 knots (75 mph, 120 km/h), with higher gusts. The minimum barometric pressure was 985 millibars (hPa; 29.09 inHg), and the cyclone was tracking west-southwest at 10 knots (11 mph, 19 km/h). Chan-hom is expected to continue strengthening steadily as it approaches the Mariana Islands over the next two days. Chan-hom is a significant threat to life and property across the Mariana Islands. Take the necessary precautions now! NEXT ADVISORY ------------------- Next complete advisory at 06:00 am JST. $$ Forecaster TheAustinMan Discussion TYPHOON CHAN-HOM DISCUSSION NUMBER 11 WIKI-HURRICANES FORECASTING CENTER 12:00 AM JST FRI JUL 03 2015 Chan-hom has begun to restrengthen after a brief hiatus in intensification yesterday. The center of circulation that was nearly exposed yesterday evening has worked its way under the convection, allowing for increased organization. Attempts at developing rainbands are evident in the northwestern quadrant of Chan-hom, and the characteristic cirrus spokes that entail improving outflow are evident in the southeast quadrant for the first time. An 0856z 89GHz pass revealed that Chan-hom had attained a complete eyewall surrounding a developing eye, though this feature has yet to appear on infrared. An AMSU pass from 12:06z indiciated that this eye opened up again, but nonetheless these microwave images suggest that Chan-hom is working against the shear and attempting to develop a succinct eye. Satellite intensity estimates currently possess a large spread as to what their intensity suggestions are, but SATCON currently stands around 63 knots. Given these indicators, Chan-hom's intensity has been shifted upwards to 65 knots, making Chan-hom a typhoon. Chan-hom has made the anticipated slowdown southeast of Guam that has been demonstrated in many of the computer forecast models. What was once Invest 94W — the low-pressure area southwest of Chan-hom that was set to complicate the forecast track — has now been absorbed by Chan-hom. Thus, the current steering for Chan-hom will largely be driven by the subtropical ridge to its north, at least momentarily, before a trough is expected to provide a weakness in the ridge, causing Chan-hom to charply curve northwestward and into the Mariana Islands. Conditions are set to improve for Chan-hom over the coming days as it enters into an area with less shear. The typhoon is still located in moderate to strong shear, but in areas just to the north and west, shear drops down to values lower than 10 knots, and in addition to favorable sea surface temperatures and oceanic heat content, anticyclonic flow and as a result favorable outflow channels will begin developing later on, and thus the intensity forecast for Chan-hom remains aggressive this advisory. The forecast track lies near model consensus, and brings the storm through the Mariana Islands. These areas should expect to see life-threatening typhoon conditions and take any necessary precautionary measures immediately. INIT 02/1500Z 10.0N 148.0E 65 KT 75 MPH 12H 03/0000Z 10.2N 147.5E 70 KT 80 MPH 24H 03/1200Z 10.8N 147.3E 75 KT 85 MPH 36H 04/0000Z 12.2N 146.9E 80 KT 90 MPH 48H 04/1200Z 13.7N 146.5E 85 KT 100 MPH ... APPROACHING THE MARIANA ISLANDS 72H 05/1200Z 16.9N 143.3E 105 KT 120 MPH 96H 06/1200Z 19.4N 140.6E 125 KT 145 MPH 120H 07/1200Z 21.0N 136.0E 140 KT 160 MPH $$ Forecaster TheAustinMan